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1.
Int J Mol Sci ; 24(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36902113

RESUMO

Aging and metabolic syndrome are associated with neurodegenerative pathologies including Alzheimer's disease (AD) and there is growing interest in the prophylactic potential of probiotic bacteria in this area. In this study, we assessed the neuroprotective potential of the Lab4P probiotic consortium in both age and metabolically challenged 3xTg-AD mice and in human SH-SY5Y cell culture models of neurodegeneration. In mice, supplementation prevented disease-associated deteriorations in novel object recognition, hippocampal neurone spine density (particularly thin spines) and mRNA expression in hippocampal tissue implying an anti-inflammatory impact of the probiotic, more notably in the metabolically challenged setting. In differentiated human SH-SY5Y neurones challenged with ß-Amyloid, probiotic metabolites elicited a neuroprotective capability. Taken together, the results highlight Lab4P as a potential neuroprotective agent and provide compelling support for additional studies in animal models of other neurodegenerative conditions and human studies.


Assuntos
Doença de Alzheimer , Neuroblastoma , Camundongos , Humanos , Animais , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Camundongos Transgênicos , Neuroblastoma/patologia , Peptídeos beta-Amiloides/metabolismo , Linhagem Celular , Cognição , Modelos Animais de Doenças
2.
Int J Mol Sci ; 18(9)2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28837064

RESUMO

Oral mucosal wounds are characterized by rapid healing with minimal scarring, partly attributable to the "enhanced" wound healing properties of oral mucosal fibroblasts (OMFs). Hepatocyte growth factor (HGF) is a pleiotropic growth factor, with potential key roles in accelerating healing and preventing fibrosis. HGF can exist as full-length or truncated (HGF-NK), NK1 and NK2 isoforms. As OMFs display elevated HGF expression compared to dermal fibroblasts (DFs), this study investigated the extent to which HGF mediates the preferential cellular functions of OMFs, and the influence of pro-fibrotic, transforming growth factor-ß1 (TGF-ß1) on these responses. Knockdown of HGF expression in OMFs by short-interfering RNA (siHGF) significantly inhibited OMF proliferative and migratory responses. Supplementation with exogenous TGF-ß1 also significantly inhibited proliferation and migration, concomitant with significantly down-regulated HGF expression. In addition, knockdown abrogated OMF resistance to TGF-ß1-driven myofibroblast differentiation, as evidenced by increased α-smooth muscle actin (α-SMA) expression, F-actin reorganisation, and stress fibre formation. Responses were unaffected in siHGF-transfected DFs. OMFs expressed significantly higher full-length HGF and NK1 levels compared to patient-matched DFs, whilst NK2 expression was similar in both OMFs and DFs. Furthermore, NK2 was preferentially expressed over NK1 in DFs. TGF-ß1 supplementation significantly down-regulated full-length HGF and NK1 expression by OMFs, while NK2 was less affected. This study demonstrates the importance of HGF in mediating "enhanced" OMF cellular function. We also propose that full-length HGF and HGF-NK1 convey desirable wound healing properties, whilst fibroblasts preferentially expressing more HGF-NK2 readily undergo TGF-ß1-driven differentiation into myofibroblasts.


Assuntos
Diferenciação Celular , Fator de Crescimento de Hepatócito/metabolismo , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Cicatrização , Biomarcadores , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/metabolismo , Técnicas de Silenciamento de Genes , Fator de Crescimento de Hepatócito/genética , Humanos , Mucosa Bucal/citologia , Mucosa Bucal/metabolismo , Isoformas de Proteínas
3.
Antioxidants (Basel) ; 12(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37507914

RESUMO

Unlike skin, oral mucosal wounds are characterized by rapid healing and minimal scarring, attributable to the "enhanced" healing properties of oral mucosal fibroblasts (OMFs). As oxidative stress is increasingly implicated in regulating wound healing outcomes, this study compared oxidative stress biomarker and enzymic antioxidant profiles between patient-matched oral mucosal/skin tissues and OMFs/skin fibroblasts (SFs) to determine whether superior oral mucosal antioxidant capabilities and reduced oxidative stress contributed to these preferential healing properties. Oral mucosa and skin exhibited similar patterns of oxidative protein damage and lipid peroxidation, localized within the lamina propria/dermis and oral/skin epithelia, respectively. SOD1, SOD2, SOD3 and catalase were primarily localized within epithelial tissues overall. However, SOD3 was also widespread within the lamina propria localized to OMFs, vasculature and the extracellular matrix. OMFs were further identified as being more resistant to reactive oxygen species (ROS) generation and oxidative DNA/protein damage than SFs. Despite histological evaluation suggesting that oral mucosa possessed higher SOD3 expression, this was not fully substantiated for all OMFs examined due to inter-patient donor variability. Such findings suggest that enzymic antioxidants have limited roles in mediating privileged wound healing responses in OMFs, implying that other non-enzymic antioxidants could be involved in protecting OMFs from oxidative stress overall.

4.
Phytomedicine ; 99: 154026, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35278903

RESUMO

BACKGROUND AND OBJECTIVES: Infected cutaneous ulcers are major health problems for children living in rural areas of Papua New Guinea. The inaccessibility of affected populations and lack of access to basic healthcare, make a local plant-based therapy an attractive treatment option. We assessed Ficus septica exudate in biological assays relevant to wound healing. We then carried out a clinical trial to determine the exudate's efficacy in healing small cutaneous ulcers compared with Savlon antiseptic cream, and soap and water washing. METHODS: Pre-clinical in vitro assessment of the exudate was carried out using assays to monitor the pro-inflammatory responses of M1 macrophages and neutrophils, antibacterial assays using known ulcer pathogens, an Ames test for mutagenicity and LC-MS chemical analysis of the exudate. An open label cluster-randomised clinical trial was performed, enrolling participants from three different clusters with skin lesions less than 1 cm in diameter. Each cluster comprising 50 participants was randomly assigned to one of three treatment arms namely topical exudate, topical Savlon antiseptic cream, and standard care (soap and water treatment), all administered daily for 2 days. The primary outcome was clinical healing/improvement measured at days 7 and 14, assessed by three dermatologists using blinded photographs. The primary analysis was assessed as non-inferiority of F. septica treatment based on the risk difference for healing/improvement. RESULTS: In vitro, the exudate which is rich in the alkaloid ficuseptine, was found to be non-mutagenic whilst also inhibiting pro-inflammatory responses and exhibiting antibacterial activity. When administered to participants enrolled in the clinical trial, no significant differences were observed between the healing efficacy of F. septica exudate and the two comparator treatments (Savlon antiseptic cream and soap/water treatment). At day 14, but not at day 7, the efficacy of F. septica exudate for healing/improving the ulcers was non-inferior to Savlon antiseptic cream or water/soap treatment. CONCLUSIONS: F. septica exudate is non-mutagenic and has both bactericidal and anti-inflammatory properties. When applied topically to small cutaneous ulcers, the exudate has a healing effect that is non-inferior to Savlon antiseptic cream and standard treatment with soap and water at day 14. Our findings, which should be confirmed in larger clinical trials, have important public health implications.

5.
Biomolecules ; 11(8)2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34439762

RESUMO

Myofibroblasts are contractile, α-smooth muscle actin-positive cells with multiple roles in pathophysiological processes. Myofibroblasts mediate wound contractions, but their persistent presence in tissues is central to driving fibrosis, making them attractive cell targets for the development of therapeutic treatments. However, due to shared cellular markers with several other phenotypes, the specific targeting of myofibroblasts has long presented a scientific and clinical challenge. In recent years, myofibroblasts have drawn much attention among scientific research communities from multiple disciplines and specialisations. As further research uncovers the characterisations of myofibroblast formation, function, and regulation, the realisation of novel interventional routes for myofibroblasts within pathologies has emerged. The research community is approaching the means to finally target these cells, to prevent fibrosis, accelerate scarless wound healing, and attenuate associated disease-processes in clinical settings. This comprehensive review article describes the myofibroblast cell phenotype, their origins, and their diverse physiological and pathological functionality. Special attention has been given to mechanisms and molecular pathways governing myofibroblast differentiation, and updates in molecular interventions.


Assuntos
Fibrose/terapia , Miofibroblastos/metabolismo , Pele/patologia , Actinas/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Cicatriz , Receptores ErbB/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Ligantes , Camundongos , Fenótipo , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Wnt/metabolismo , Cicatrização , beta Catenina/metabolismo
6.
Front Nutr ; 8: 778289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901123

RESUMO

The anti-inflammatory and cholesterol lowering capabilities of probiotic bacteria highlight them as potential prophylactics against chronic inflammatory diseases, particularly cardiovascular disease. Previous studies in silico, in vitro, and in vivo suggest that the Lab4 probiotic consortium may harbour such capabilities and in the current study, we assessed plasma levels of cytokines/chemokines, short chain fatty acids and lipids and faecal levels of bile acids in a subpopulation of healthy Wistar rats included in 90-day repeat dose oral toxicity study. In the rats receiving Lab4, circulating levels of pro-inflammatory interleukin-6, tumour necrosis factor-α and keratinocyte chemoattractant/growth regulated oncogene were significantly lower compared to the control group demonstrating a systemic anti-inflammatory effect. These changes occurred alongside significant reductions in plasma low density lipoprotein cholesterol and increases in faecal bile acid excretion implying the ability to lower circulating cholesterol via the deconjugation of intestinal bile acids. Correlative analysis identified significant associations between plasma tumour necrosis factor-α and the plasma total cholesterol:high density lipoprotein cholesterol ratio and faecal levels of bifidobacteria in the Lab4 rats. Together, these data highlight Lab4 supplementation as a holistic approach to CVD prevention and encourages further studies in humans.

7.
Fitoterapia ; 141: 104478, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927016

RESUMO

The sap of the tree Lepiniopsis ternatensis is used as a topical treatment for cutaneous leg ulcers in Papua New Guinea. This study, which is the first investigation of this medicinal plant, examines the effect of the sap on wound healing biology using human-derived primary cell lines. NMR spectra from 1D and 2D experiments revealed the sap to contain a single major component, identified as the polyphenol, trifucol. The sap significantly increased the proliferation of dermal fibroblasts at just 1.3 µg/ml, without influencing keratinocytes, suggesting a fibroblast-specific mechanism of stimulation. It also significantly inhibited TNF-α secretion by pro-inflammatory M1 macrophages, but not from neutrophils, at 130 µg/ml. The low toxicity of the sap towards dermal cells along with its fibroblast stimulation activity and downregulation of macrophage TNF-α makes it a potentially attractive agent to promote dermal wound healing in chronic non-healing ulcers.


Assuntos
Apocynaceae/química , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Etnobotânica , Humanos , Macrófagos/metabolismo , Papua Nova Guiné , Plantas Medicinais , Polifenóis/química , Fator de Necrose Tumoral alfa/genética , Cicatrização
8.
Fitoterapia ; 143: 104554, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32184096

RESUMO

Cypholophus macrocephalus sap is used to treat bacterially infected cutaneous leg ulcers in Papua New Guinea. High resolution LC-MS analysis of the sap revealed it to be rich in sulphated flavonoids. We assessed the effects of the sap on the differentiation and pro-inflammatory anti-microbial responses of M1 macrophages using IL-6 and TNF-α ELISAs and found significant increases in M1 macrophage IL-6 expression with concentrations as low as 243 ng/ml sap. Neutrophil IL-6 and TNF-α expression was also significantly increased but to a lesser degree. Matrix metalloproteinases (MMPs) 1, 2, 8 and 9 which are known to contribute to the toxic nature of wound exudates were inhibited by the sap at 24 µg/ml. The sap was tested with several bacterial species known to colonize cutaneous ulcers in Papua New Guinea but proved not to be active. Cypholophus sap stimulates pro-inflammatory, anti-microbial M1 macrophage and neutrophil responses at very low concentrations, whilst also inhibiting MMPs. The combination of an enhanced innate immune response and inhibition of MMPs in ulcer exudate, may contribute to the eradication of bacteria and healing of these infected ulcers. The sap concentrations used in these assays are readily achievable in an in vivo context.


Assuntos
Preparações de Plantas/uso terapêutico , Úlcera Cutânea/tratamento farmacológico , Urticaceae/química , Cicatrização , Adulto , Antibacterianos/farmacologia , Citocinas/metabolismo , Etnobotânica , Humanos , Macrófagos/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz/farmacologia , Metaloproteinases da Matriz/metabolismo , Testes de Sensibilidade Microbiana , Neutrófilos/efeitos dos fármacos , Papua Nova Guiné , Úlcera Cutânea/microbiologia , Adulto Jovem
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